<template>
  <div class="component-upload-image" :style="{ '--width': width, '--height': height }">
    <el-upload :multiple="multiple && limit !== 1" :action="uploadImgUrl" :list-type="listType"
      :on-success="handleUploadSuccess" :before-upload="handleBeforeUpload" :limit="limit" :on-error="handleUploadError"
      :on-exceed="handleExceed" ref="imageUpload" :before-remove="handleDelete" :headers="headers" :file-list="fileList"
      :on-preview="handlePictureCardPreview" v-bind="$attrs">
      <slot>
        <el-icon class="avatar-uploader-icon" v-if="showIcon">
          <plus />
        </el-icon>
      </slot>
      <slot slot="trigger" name="trigger" />
    </el-upload>
    <!-- 上传提示 -->
    <slot name="tip">
      <div class="el-upload__tip" v-if="showTip">
        请上传
        <template v-if="fileSize">
          大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
        </template>
        <template v-if="fileType">
          格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b>
        </template>
        的文件
      </div>
    </slot>

    <el-dialog v-model="dialogVisible" title="预览" width="800px" append-to-body>
      <img :src="dialogImageUrl" style="display: block; max-width: 100%; margin: 0 auto" />
    </el-dialog>
  </div>
</template>

<script setup>
import { getToken } from "@/utils/auth";
import { genFileId } from 'element-plus'

const props = defineProps({
  modelValue: { type: Array, default: () => ([]) },
  // 图片数量限制
  limit: {
    type: Number,
    default: 10,
  },
  // 大小限制(MB)
  fileSize: {
    type: Number,
    default: 5,
  },
  // 文件类型, 例如['png', 'jpg', 'jpeg']
  fileType: {
    type: Array,
    default: () => ["png", "jpg", "jpeg", 'pdf'],
  },
  width: { type: String, default: '100px' },
  height: { type: String, default: '100px' },
  // 是否显示提示
  isShowTip: {
    type: Boolean,
    default: true
  },
  listType: { type: String, default: 'picture-card' },
  // 是否支持多选文件
  multiple: {
    type: Boolean,
    default: true
  },
  // 是否显示图标
  showIcon: {
    type: Boolean,
    default: true
  },
  uploadImgUrl: { type: String, default: import.meta.env.VITE_APP_BASE_API + 'v1/base/upload' }, // 上传的图片服务器地址
});

const { proxy } = getCurrentInstance();
const emit = defineEmits(['update:modelValue'])
const number = ref(0);
const uploadList = ref([]);
const dialogImageUrl = ref("");
const dialogVisible = ref(false);
const headers = ref({ Authorization: "Bearer " + getToken() });
const showTip = computed(
  () => props.isShowTip && (props.fileType || props.fileSize)
);

const fileList = computed({
  get() {
    return (props.modelValue || []).map(url => {
      const name = url.slice(url.lastIndexOf("/") + 1)
      return { name, url }
    })
  },
  set(val) {
    emit("update:modelValue", val.map(d => d.url))
  }
})

// 上传前loading加载
function handleBeforeUpload(file) {
  let isImg = false;
  if (props.fileType.length) {
    let fileExtension = "";
    if (file.name.lastIndexOf(".") > -1) {
      fileExtension = file.name.slice(file.name.lastIndexOf(".") + 1);
    }
    isImg = props.fileType.some(type => {
      if (file.type.indexOf(type) > -1) return true;
      if (fileExtension && fileExtension.indexOf(type) > -1) return true;
      return false;
    });
  } else {
    isImg = file.type.indexOf("image") > -1;
  }
  if (!isImg) {
    proxy.$modal.msgError(
      `文件格式不正确, 请上传${props.fileType.join("/")}图片格式文件!`
    );
    return false;
  }
  if (props.fileSize) {
    const isLt = file.size / 1024 / 1024 < props.fileSize;
    if (!isLt) {
      proxy.$modal.msgError(`上传头像图片大小不能超过 ${props.fileSize} MB!`);
      return false;
    }
  }
  proxy.$modal.loading("正在上传图片，请稍候...");
  number.value++;
}

// 文件个数超出
function handleExceed(files) {
  if (props.limit === 1) {
    const imageUpload = proxy.$refs.imageUpload
    imageUpload.clearFiles()
    const file = files[0]
    file.uid = genFileId()
    imageUpload.handleStart(file)
    imageUpload.submit()
  } else {
    proxy.$modal.msgError(`上传文件数量不能超过 ${props.limit} 个!`);
  }
}

// 上传成功回调
function handleUploadSuccess(res, file) {
  const { file_preview } = res.data[0]
  if (res.code === 200) {
    if (props.limit === 1) {
      uploadList.value = [{ name: file_preview, url: file_preview }]
    } else {
      uploadList.value.push({ name: file_preview, url: file_preview })
    }
    uploadedSuccessfully();
  } else {
    number.value--;
    proxy.$modal.closeLoading();
    proxy.$modal.msgError(res.message);
    proxy.$refs.imageUpload.handleRemove(file);
    uploadedSuccessfully();
  }
}

// 删除图片
function handleDelete(file) {
  fileList.value = fileList.value.filter(d => d.name !== file.name)
  return false
}

// 上传结束处理
function uploadedSuccessfully() {
  if (number.value > 0 && uploadList.value.length === number.value) {
    fileList.value = props.limit === 1 ? uploadList.value : fileList.value.filter(f => f.url !== undefined).concat(uploadList.value);
    uploadList.value = [];
    number.value = 0;
    proxy.$modal.closeLoading();
  }
}

// 上传失败
function handleUploadError() {
  proxy.$modal.msgError("上传图片失败");
  proxy.$modal.closeLoading();
}

// 预览
function handlePictureCardPreview(file) {
  dialogImageUrl.value = file.url;
  dialogVisible.value = true;
}
</script>

<style lang="scss">
// .el-upload--picture-card 控制加号部分
.component-upload-image {
  // .hide .el-upload--picture-card {
  //   display: none;
  // }

  .el-upload--picture-card {
    width: var(--width);
    height: var(--height);
  }

  .el-upload-list--picture-card .el-upload-list__item {
    width: var(--width);
    height: var(--height);
  }

  .is-disabled {
    .el-upload--picture-card {
      cursor: no-drop;
    }
    .el-upload-list__item{
      display: none;
    }
  }
}
</style>